Two referees are old-hat. Down under they're considering coaches challenges, and introducing it in the Toyota Cup next year I believe. Coach gets a few opportunities a game to challenge a referee decision(or non decision, ie something a ref missing in play), with referees looking at replays in the same way they would a possible try. Similar to what they've got in NFL and other sports.

Maybe we'll see it in the SL in 5 years

Wouldn't that require even more match officials though? It's hard to see where they are going to come from, especially if they have to be full time.

My own opinion is that while I think quite a few refs don't appear to be at a high standard they tend to be the younger ones and it just seems like they are asked to step up far too early in their careers. There doesn't seem to be a huge pool of potential officials to choose from so it's probably something that we just have to put up to some extent.
Reversing the decision to make officials full time might be a good place to start though, and I think the ref's have been getting steadily worse since Cummings took over as well as the laws and interpretations becoming more ambiguous and altered for no clear purpose.

I think with two referees, even if they aren't as high a standard individually as one current SL ref, they will collectively be better as they will have an extra pair of eyes on the field.

I do agree about Cummins though. I think appointing a poor referee to administer all referees was ultimately going to be a bad decision. His ideas of changing interpretations and focusing on one rule for a few weeks have been quite simply ridiculous.
I also agree that going full time has also not worked. And not only has it not made a better improvement, but it's turning away potential decent referee's who do not want to be full time.

I don't think the introduction of 2 refs would do anything to improve refereeing decisions from the perspective of the strident boneheads who sit down to watch a match with their minds already made up that the ref is biased against their team, and made a thousand bad decisions, and was "very poor", before the match ever kicks off.

The standard or refereeing is actually very high, and invariably if you watch any game again in analytical mode in the cold light of day, you will find much less to complain about, and much more even-handedness, than you thought. This is normal - when i am watching my team, I am entirely biased at them, and badly want them to win, and shouting at the opposition and the officials is just part of going to a game and getting involved, for me. But I do not obsess about the refereeing, on the contrary, I accept that in most games the ref played a big part in the spectacle I just watched.

Yes we have had some howlers, though tbf these tend to be more VR howlers than on-the-pitch, but that is only a result of refs being mere mortals, like the rest of us. This guff about refereeing standards being very bad is just emperor's new clothes from people with chips on their shoulders, or axes to grind, who can't wait to get up an indignant head of steam.

I watch the NRL on Premier, and don't think that having 2 referees has made any difference to the amount of stick officials get or the amount of whingeing from coaches, or accusations of incompetence or bias from fans. The main differences are that the usual commentators don't seem to have highlighting perceived bad calls as a mission, and have the capacity to get over what might have been an incorrect call and concentrate instead on the game. Stevo has a lot to answer for. His disdain for referees, even if it is scripted as a music-hall ex-forward comedic effect, is actually part of the problem.

Having said all that, I am in favour of 2 referees for a number of reasons. First, once the refs themselves got used to it, (which took at east a year), games must have got physically easier for them to control, and anyone in any job who is less knackered will tend to perform a bit better. Secondly, you can hardly argue against the principle that one ref at the PTB and one in the defensive line can't keep a better eye on both than a single ref. But mainly because it would mean that there would have to be created a significantly larger pool of first class referees, and the more of them there is, the better a career choice becoming a referee appears to those who might be interested, and so your chances of attracting more and better candidates are increased.

And what about the neutrals? Presumably anyone watching a game as a neutral who feels the refereeing isn't up to scratch must be an ardent ref hater who only watches the games so they can complain about referees?
You could repeat what you just wrote at any time about any officials in any sport. You could quite easily say that all officials in any sport are absolutely brilliant and anyone who disagrees must have an axe to grind of be biased.
However, presenting opinion as if it were fact doesn't count as proof for either side of this argument.

Influence by the media and supporters.